In rotating machinery where coils are wound by distributed winding into many slots formed so as to be open to the inner periphery side of a stator core, an alternating current is supplied to the stator coils to generate a rotating magnetic field in the stator, and rotating torque is generated in a rotor by the rotating magnetic field.
As examples of such rotating machineries, there are an induction motor using a cage induction motor rotor and a synchronous motor using a permanent magnet as a rotor. These induction motor and synchronous motor can be utilized also as generators, and therefore by the rotating machinery or machinery as referred to herein, it is meant to include both such induction motor and synchronous motor.
Patent Literature 1 (Japanese Patent Laid-Open Publication No. 2006-211810) shows an example of the above rotating machinery. The rotating machinery shown therein has a rotor core provided with many slots which are open to the inner periphery side and in that rotating machinery a plurality of generally U-shaped segment coils are inserted into each of the slots. According to the description of Patent Literature 1 the rotating machinery disclosed therein is advantageous in that it can be reduced in size and weight.
In rotating machineries of the type in which generally U-shaped segment wires are inserted into each of the aforesaid slots, including the rotating machinery disclosed in Patent Literature 1, it is necessary that respective ends of the segment wires be connected by welding, and this point remains to be solved in point of improving the productivity.
It is an object of the present invention to provide rotating machinery superior in productivity.